Friday, April 12, 2013

To Jump

    As I have mentioned in a previous post, spring is coming here in Oklahoma and several groups of insects are starting to come out. One of the more numerous groups of insects out there are the beetles (Coleoptera), and they are starting to creep out of their overwintering shelters or hatch out of their eggs for a brand new year!
    One of the beetles I saw starting to show up on campus here at the University of Oklahoma is a shiny green metallic and red flea beetle called Kuschelina gibbitarsa. It is part of a group of beetles called the flea beetles because they have a very strong "jumping" mechanism to get escape predators. If you look closely at these beetle's hind legs, you'll notice that the femora (longest parts of the leg, kind of like our femur) are really wide and "fat", because they have lots of muscles in there to help them push off into the air when threatened. These small to medium-sized beetles feed on plants, many beetles in fact feed on one or two types of plants only!
Examples of other types of flea beetles. Image by James Lindsey at Ecology of Commanster
      All flea beetles are part of the beetle tribe Alticini, named after the beetle genus Alticus. Altus in Latin means "high", which is in reference to their high jump. Other words that use "alt" like the Alticini are "altitude", "altimeter", etc. Actual fleas on the other hand, the Siphonaptera, do not get their name for their jumping but their siphon-like mouth parts and lack of wings (siphon+aptera, aptera meaning lack of wings). Fleas are much better jumpers than flea beetles (see a really neat article about flea jumping abilities here from the BBC), but flea beetles are still pretty impressive with how high and fast they can jump!
      So, if you're walking around campus this spring and you see something spring from a plant really quickly, it could be one of these flea beetles! Have a great weekend everyone!

Monday, April 1, 2013

Spring is Springing!

Our weather this month in Oklahoma has been funky, to say the least. In this state we're pretty used to huge swings of temperature in short period of time depending on which winds are strongest (warm from the south, cold from the north). They are so strong that, during the months of March-May, we have our annual Tornado season. We haven't had any tornadoes yet, but we did have a pretty nasty hail storm this past weekend. I won't go too far into weather patterns (we have a whole meteorology department here at OU for that, as well as the National Weather Service), or talk too much about global warming (its a fact...whether you believe it or not is up to you), but the fact of the matter is we've hit our Oklahoma spring, and hit it hard.
     The trees have started to bud-out, and the oakes have put out their pollen panicles...the start of flowers and leaves and plant growth for spring. This means that soon all the insects will also be out in full-swing, since many depend on the plants and trees for the first doses of nutrition to power the first generations of insects. This is especially true for groups of insects like aphids, and my study group of insects, the plant bugs (Miridae). Both depend on new-growth leaves and tissues to get the sugary sap, and nutritious plant-cells to grow and develop, so the temperatures and day light start triggering the overwintering eggs of these insects to hatch. Soon it will be a few weeks of boom or bust feeding, growing, dispersing, laying eggs, and then repeating.
Pine aphids. From Landscape IPM Advisory website at Utah State
      I took one of my volunteers out into the field behind the museum to show him the methods of collecting insects and what to expect for insects this time of year, and one of the most prominent bugs already out are massive swarms of aphids feeding on the pine trees. Aphids are interesting because they are one of the insect groups that have live-births (viviparity), and also have cloning (parthenogenesis). Especially in the spring, to take advantage of the plant growth and hopefully not have populations completely eaten by predators, there is pressure to produce as many aphids as possible and as quickly as possible. So, rather than wait around for a mate for sexual reproduction, many aphids will just clone copies of themselves in mass, producing huge populations of identical individuals. Later in the season aphids will switch to sexual reproduction and produce males and females, but right now on the pines its swarms of females.
Aphid reproduction. Image from San Fransisco State University Lab website.
         So, if you are walking around campus lately, take a look at the insects that are also coming out at the same time. I bet you'll see a few aphids, and soon the tide will start of all kinds of really neat and interesting insects starting their yearly cycle of life. Have a good week!